Railroad hopper cars have been employed for years to transport particulate and granular materials, such as grain. Typically, a car is loaded through the use of overhead chutes that extend through one or more hatches or troughs formed in the top of the car.
One type of common hopper car presents a continuous trough extending substantially the length of the car which communicates with the top of the car and is closed during transport by a series of longitudinally extending end-to-end hatch covers. Each cover may be of from eight to thirteen feet in length and weigh on the order of 100 pounds. Some hopper cars include smaller port covers in addition to the main hatch covers, the port covers overlapping the adjacent main hatch covers as shown and described in U.S. Pat. No. 5,517,925 and incorporated herein by reference.
The hatch arrangements described above do not provide a means to gain access to the trough without manually raising the large, heavy hatch covers. Furthermore, this process can be very dangerous and requires the use of running boards installed along the sides of the cars at a height to provide access to the covers.